It is known to use proximity-sensors, such as ultrasonic-sensors, to determine whether a parking-space will accommodate a host-vehicle. For a typical automated parallel-parking maneuver, the rear-end of the host-vehicle must be positioned forward of the open parking-space to allow the proximity-sensor to detect a corner of a parked-vehicle adjacent to the host-vehicle. This positioning may allow following-traffic to encroach on the zone adjacent to the open parking-space preventing the host-vehicle from executing the parking-maneuver.